Brother Fax-Capable Machines and VoIPAll fax-capable Brother machines (Intellifax and Multi-Function
Centers) are designed to operate on a Public Switched Telephone Network (PSTN). This is
the historically common analog telephone system. Currently, another type of telephone service
is becoming common - Voice over Internet Protocol (VoIP). VoIP is frequently referred
to as a Digital or Internet Phone.

The main difference between the two is that a PSTN connection is a direct, dedicated link
between the two calling stations while VoIP divides the call up into data "packets"
and transmits them over the Internet. For consistent, reliable service Brother recommends
the use of a PSTN line. While Brother products are capable of functioning over a VoIP system,
the unregulated nature of the Internet may cause situations that result in
unsatisfactory performance.

Symptoms of common problems that are not normally related to faxing over VoIP:

No dial tone.

Fax machine will not answer.

For help with these problems, please go to our online Support Center,
select your model and click "Go." On the Frequently Asked Questions tab,
search for "No Dial Tone" or "Answer mode".

Symptoms of common problems that may be related to faxing over VoIP:

Fax call starts and receiving machine answers but will not connect.

Fax call is received and machine answers but will not connect.

Call (sending or receiving) connects and transmission starts but then disconnects.

Call (sending or receiving) connects and transmission starts but only 1 or 2 pages
are sent before call disconnects.

Faxes will not complete at certain times of day but work fine at other times.

Faxes will not complete to certain phone numbers but work fine with other numbers.

Please follow the steps below (Improving results) for these issues.

Improving Your Results with VoIPThere are several steps you can take that may improve your
results when using a Brother fax-capable machine on a VoIP line. Please note Brother does not
guarantee these steps will provide satisfactory performance.